1. Field of the Invention
The present invention relates to a hard magnetic material having excellent hard magnetic characteristics.
2. Description of the Related Art
Materials generally known as hard magnetic materials having performance superior to ferrite magnets and alnico magnets (Al--Ni--Co--Fe system magnets) include a Sm--Co system magnet, a Nd--Fe--B system magnet, and the like.
The Nd--Fe--B system magnet is a magnet having high coercive force (iHc), remanent magnetization, and maximum magnetic energy product ((BH).sub.max), and excellent hard magnetic characteristics, but has a problem in that since its magnetic characteristics greatly vary with temperature, it cannot be used as a constituent material for a sensor or the like, which is used at high temperatures.
The Sm--Co system magnet causes less changes in magnetic characteristics with temperature, but has a problem in that since coercive force (iHc) is lower than that of the Nd--Fe--B system magnet, hard magnetic characteristics deteriorate, particularly when it is used for a small device such as a motor, an actuator, or the like.